294: MORPHOLOGY AND EVOLUTION
Gasserian ganglion. In the Chimpanzee the ophthalmic division courses as in Man, and breaks up into lachrymal, frontal and nasal nerves. The lachrymal nerve, lying between the wall of the orbit and the external rectus
muscle, supplies the lachrymal gland, conjunctiva and skin of the eyelids. The frontal nerve breaks up into supra-orbital and supra-trochlear nerves which are as in Man.
The nasal nerve is- distributed as in Man; its lateral terminal branch is large. The superior maxillary and inferior maxillary divisions of the trigeminal nerve are as in Man, but I was unable to detect as many branches radiating from Meckel's ganglion. The chorda tympani joins the inferior maxillary division or its lingual branch.
Ganglia connected to the Trigeminal Nerve.—
The ciliary ganglion is larger than in Man in the Chimpanzee. It receives branches from both divisions of the third nerve, the naso-ciliary nerve and the sympathetic plexus on the internal carotid artery.
It gives off short ciliary nerves to the eyeball; one of these divides into upper and lower divisions which enter the globe.
The subinaxillary ganglion is fused with the hypoglossal nerve.
MeckePs ganglion is placed as in Man. The otic ganglion was not definitely isolated.
Abducens Nerve,—The sixth cranial nerve is as in Man.
Facial Nerve.—The facial nerve courses as in Man. It is most complex in Man and the Orang, simplest in the Chimpanzee, and intermediate in complexity in the &orilla. In the Chimpanzee it gives off a posterior